code: def test_forward_gpu_cpu(self):
      cpu_res = self.get_result(
          cuda.to_cpu(self.input), cuda.to_cpu(self.gt)
      )
      gpu_res = self.get_result(
          cuda.to_gpu(self.input), cuda.to_gpu(self.gt)
      )
      for idx in range(len(gpu_res)):
          gpu_res[idx].to_cpu()
          numpy.testing.assert_almost_equal(
              cpu_res[idx].data, gpu_res[idx].data
          )
  
file_path: chainer/tests/chainer_tests/functions_tests/loss_tests/test_discriminative_margin_based_clustering_loss.py
imports: import unittest
  import numpy
  import chainer
  from chainer.backends import cuda
  from chainer import functions
  from chainer import gradient_check
  from chainer import testing
  from chainer.testing import attr
label_desc: Use image node_id 7 for calling the TestDiscriminativeMarginBasedClusteringLoss obj's underlying member method code with example usage: obj.test_forward_gpu_cpu() without return types